Process for improving vegetable textile material



Patented Nov. 10, 1931' LEON nrn'rnnrrmn, or VIENNA, AUSTRIA PROCESS FOR IMPROV'fNG VEGETABLE TEXTILE MATERIAL No Drawing. Application filed June 16, 1927, Serial No. 199,410, and in Austria May 3, 1927.

It is known that b treatment with alkali and carbon bisulphi e vegetable textile materials acquire valuable properties which, ac-

, cording tothe conditions of treatment, find 6 expression in a silky lustre or a finish, or in "both (see German patent specification No. 129883, Austrian patent specifications Nos. 100194 and 101300 and British specifications Nos. 19912 of 1901, 157 2 of 1915 and 168575).

The intensity of lustre which can be obtained by the processes hitherto used is, however, limited in degree, because if this degree is overstepped the thread or fabric under treatment becomes stiff, and thus loses its natural soft feel and is more or less hard and pi er-like tothe touch.

a he present invention rests on the obser-.

vation that particularly remarkable effects in respect of lustre or finish without deterioration of feel may be obtained by, subject"- ing the fabric or yarn, which has been treated with alkali and carbon bisulphide, before it is brought into contact with an agent that precipitates viscose, to the actionof a solvent for cellulose xanthate.

b If stretching be applied during the Whole course of the process, or during that phase thereof which is suitable, there is obtained a silky lustre which exceeds considerably that obtainable by the usual mercerization process and at the same time the feel of the fabric or yarn is not substantiall affected.

When the operation is con ucted without any stretching, or the material allowed to shrink after or during the operation and the shrinkage is permitted to continue throughoutthe operation up to the finishing stage, or at least during a suitable phase of the operation, the fabric or yarn acquires a woolly condition.

Considering that the lustre obtainable with the aid of alkali and carbon bisulphide must be supposed to be due not only to the mercerizing effect of the alkali solution but also ,to the simultaneous effect of the carbon bisulphide, that is to say the conversion, at least superficially, of the yarn or fabric into cellulose xanthate, it is surprising that this diminished by treatment with the solvent for .thate by an intimate sorption between fibre lustre is not diminished 'or not appreciably the cellulose xanthate. It remains uncertain whether this circumstance'is to be attributed to an inhibition or weakening of the dissolving action of the solvent for cellulose xanand viscose, or to a precipitation in art of theviscose formed within or on the bre by any non-cellulosic substance contained in the fibre, that is to say the reconversion of such viscose into cellulose, or finally to the removal, together with the dissolved xanthate, of the outer layer of the fibre having adhering to it certain roughnesses which affect the lustre;

In carrying out the process the fabric or yarn which has been treated with alkali and carbon bisulphide is subjected, without first bringing it into contactwith an agent which precipitates viscose with regeneration of cellulose, to the action of a solvent for cellulose xanthate As suitable solvents may be named water or,- preferably, a solution of a basic substance, such as caustic alkali or an alkali salt having an alkaline reaction, :such as borax, an alkali sulphide, an alkali phosphate, an alkali acetate or an alkali carbonate, or a solution of an alkali sulphide in a caustic alkali solution, or a solution of a neutral salt which does not decompose viscose, such as common salt, ora dilute solution of an acid which does not precipitate viscose, such as acetic acid or sulphurous acid. After the treatment with the solvent for cellulose xanthate the yarn or fabric may, optionallyafter being washed, be brought into contact with any of the precipitating agents for viscose known in the viscose art and may then be washed and finished in known manner, or it may be directly washed and finished.

The following examples illustrate the invention, the parts being by weight Emample 1.--Bleached or unbleached cot- 'ton fabric orv cotton yarn is treated inv stretched condition with caustic soda solu.' tion of 18 to 22.5 percent. strength at 15 to 20 C. and is then immediately, or after having remained a short or long time in the caustic soda solution (in some cases after removal of the excess of the caustic soda solution by: pressing or centrifuging), .sub

of common salt.

jected to the action of carbon bisulphide vapour or of liquid carbon bisulphide either alone or mixed with a suitable diluent (for instance a solution of 0.5 to 10 per cent. strength of carbon bisulphide in benzene) for a few seconds up to 10 minutes or longer, for example up to 2 to 5 hours. The yarn or fabric, in some cases after removal of the excess of carbon bisulphide by a current of air or evacuation, is then brought into caustic soda solution of 5 to 18 per cent. strength at 15 to 18 C., or into an aqueous solution of sodium sulphide of 8 to 30 per cent. strength, or into a liquid containing 10 to 20 per cent. of caustic soda and 10 per cent. of sodium sulphide, or into a solution of sodium carbonate of 10 per cent. strength, or into a dilute solution, say of 5 per cent. stren th,

In the solvent for cellulose xanthate the yarn or fabric remains for 5 minutes up to 2 hours, whereupon it is washed and then transferred to a bath which precipitates viscose. The latter may be any precipitating bath known in the viscose art, for'instance sulphuric acid of 10 per cent; strength or hydrochloric acid of 4 to 6 per cent. strength, or a'solution of 4 parts of sodium bisulphate and 7 parts of sulphuric acid of 66 Baum in. 6 parts of water, or a solution of 2 parts of ammonium chloride, 2 parts of sulphuric acid of 66 B. and 2 parts of glycerine in 14 parts of water, or

a solution of 15 parts of sodium sulphate.

1 part of zinc sulphate, 7 parts of glucose and 8 parts of sulphuric acid of 66 B. in 69 arts of Water. The precipitating bath may e used at room temperature or at raised temperature, such as 50 C. After the yarn or fabric has remained for a shorter or longer time in the. precipitating'bath it is washed and dried.

'Instead of a precipitating bath, another agent precipitating viscose, for example heat or steam may be employed.

Before or after the washing the yarn or fabric may be desulphuriaed in known manner, for example by treatment with a solution of sodium sulphide, or may be bleached, or may be treated by both operations.

The finished product is characterized by a highly silky lustre and an agreeable feel.

E wample 2.-Mode of operation as in Example 1, with the difference that the fabric:

or yarn, after having been treated with the solvent for cellulose xanthate is, without being Washed, transferred to the viscose precipitating bath E wample 3.The mode of operation is th same as in Example 1, with the difference that water is used as the solvent for cellulose xanthate.

E ammple 4. -The operation is the same as that in Example 1 or 2, with the difference that the yarn or fabric, after it has been treated with the solvent for cellulose xanthate, is only washed and dried.

E wample 5.The operation is the same as in Example 1, 2, 3 or 4, with the difference that the goods are not stretched during the treatment with the caustic soda solution but only beginning with the treatment with carbon bisulphide. i

E wample 6.-The operationis the same as in Example 1, 2, 3, 4 or 5, with the difference that the fabric or yarn is released from stretch before being washed.

Example fr-The operation is the same as in Example 1, 2, 3, 4 or 5, with the difference that the stretching is discontinued before drying.

In Examples 2, 3, 4, 5, 6 and 7 the product is also a highly silky material of soft feel.

E trample 8.The operation is the same as in Example 1, 2, 3 or 4, with the difference that the fabric or yarn is not stretched during the Whole operation.

The result is a product which has a very full feel and woolly condition.

Ema-222. 276 9.The operation is the same as in Example 1, 2, 3, 4 or 5, with the difference that the stretching is discontinued before the treatment with the cellulose xanthate solvent. The result is a soft fabric or yarn of woolly character.

Example 10.-The operation is the same as in the foregoing examples, but with the difference that the mercerizing liquor contains only 9 to 12 per cent. of caustic soda.

Eaam-ple 11.'Bleached or unbleached cotton fabric or cotton yarn is treated in stretched condition with undiluted carbon bisulphide or with carbon bisulphide diluted with benzene (for instance 1- to 5 parts of benzene to 1 part of carbon bisulphide) for a few seconds up to a quarter of an hour. Then, if necessary, after expressing or centrifuging the excess of carbon bisulphlde, the fabric or yarn is treated with caustic soda solution 'of in Example 11, with the difference that thestretching is discontinued before drying.

The products obtained in accordance with Examples 11 to 14 are similar in appearance and feel to those obtained in Examples 1 to 6. Example 1-5..The operation is the same as in Example 11, with the difference that the described in fabric or yarn is not str etched during the V whole operation.

' Example 16.The operation is the same as in Example 11 or 12, with the difference that the stretching is discontinued before the treatment with the solvent for cellulose xanthate. In Examples 15 and 16 there is obtained a yarn or fabric of woolly condition.

Example 1'/ .Bleached or unbleached cotlq ton yarn or cotton fabric is treated in stretched condition with undiluted or diluted carbon bisulphide for several seconds upto 15 minutes. The fabric or yarn, if desired,

after'removal of the excess of carbon bisulhide by squeezing or centrifuging, is then EwampZe 18.The operation is the same as in. Example 17, with the difference that the in Example 17 or 18, with the difference that the stretchlng is applied after the treatment varn or fabric after the treatment with caron bisulphide is treated with .caustic soda solution of 15 to per cent. strength, for ex-' ample of 18 per cent. strength, at '15 to 20 C. for several minutes up to 2 hours or even longer and is then brought into a caustic soda solution oflO per cent. strength, cooled to 0 to 10 and allowed to remain therein for several seconds up to 10 minutes.

Emample 1.9.-The operation is the same as with carbon bisulphide.

Example 20.-The operation is the same as in Example 17 or 18, with the differencethat the stretching is discontinued before the introductlon into the viscose precipitating bath. Eat-ample 21.-The operation is the same as 1n Example 17 or 18, with the difference that g the stretching is discontinued before drying.

The products obtained in accordance with Examples 17 to 21 are similar in respect to the appearance and feel to those obtained in accordance with Examples 1 to 6.

Example 22. The-operation is the same as in Example 17 or 18, with the difference that the fabric or yarn is not stretched during the whole operation.

Ewwmple Z3.-The operation is the same as in Example 17, 18 or '19, with the difference that the stretching is discontinued before the treatment with the solvent for cellulose xant-hate. r

In Examples 22 and 23 there is obtained a-yarn or fabric of woolly condition.

The cotton fabric or yarn treated in accordance with the invention, may be in the raw condition or preliminarily treated (for example boiled or keired by any known meth- 0d), wetted or not wetted, mercerized or not mercerized. It may also be preliminarily treated with a hydrolyzing or gelatinizing agent, for instance a strong mineral acid, such as sulphuric acid of 49 to B., or phosphoric acid of 55 to 57 B., or over, or hydrochloric acid of 24; B.,- or nitric acid of 43 to 46 Be. or over, or hot zinc chloride solution of 60 B., or cupric oxide ammonia solution of high concentration.

The expression vegetable textile material in the specification and in the claims includes wherever the context permits, all vegetable textile materials, such as flax, linen, hempf, ramie-fibre, jute and particularlyvcotton and the like, in the form of pure vegetable fabrics (for example pure cotton fabrics) or mixed fabrics or in the form of yarn in skeins, cops, or warps.

The finished products may be calendered, schreinered, beetled or similarly treated.

The production of patterned effects by use of reserves is an obvious procedure.

I claim. 1 r

1. The process of improving the lustre or finish ofvvegetable textile material which has been treated with caustic alkali and carbon bisulphide to form cellulose xanthate which comprises subjecting the said so treated material to the action of a solvent for cellulose xanthate before it is subjected to the action of an agent capable of precipitating viscose.

2. The process of improving the lustre or" finish of vegetable textile material which has been treated with caustic alkali and carbon bisulphide under conditionsv forming cellulose xanthate which comprises subjecting the said so treated material to the action of an agent which is a solvent for the cellulose xanthate so formed, the said so treated material being subjected to said agent before the said so treated material is subjected to an agency capable of regenerating cellulose from cellulose xanthates.

3. The process of improving vegetable textile material which has beensubjected to the action of caustic alkali solution and carbon disulphide which comprises subjecting the so treated material, before it is subjected to an agency regenerating cellulose, to the ac- .tion of a basic substance capable of dissolving cellulose xanthate.

4. The rocess of improving vegetable texso treated material, before it is subjected to an agency regenerating cellulose, to the action of a solution containing caustic alkali and alkali sulphide in such concentrations as to be capable of dissolving cellulose xanthate.

6. The process of improving the lustre or finish of vegetable textile material which comprises subjecting said material to the acmy hand.-

tion of-carbon bisulphide and caustic alkali, and thereafter, before treatment with an agent capable of regenerating cellulose from viscose, subjecting the said treated material t}? the action of a solvent for cellulose xant ate'.

finish ofvegetable textile material which comprises converting it superficially into cellulose xanthate and before treatment with an agent capable of regenerating cellulose from cellulose xanthate subjecting the said superficially converted material to the action of a solvent for cellulose xanthate.

8. The process of improving vegetable textileimaterial which comprises converting it at least-superficially into cellulose Xanthate and before subjecting it to an'agency capable of regenerating cellulose from cellulose xanthate subjecting the so converted material to the action of a solvent for cellulose Xanthate in a a step separate from the step of conversion into cellulose xanthate.

In testlmony whereof I have hereunto set LEON LILIENFELD.

7. The process of improving the lustre 0r 

